These are so confusing, can someone explain how to do this

Apack of gum would be considered a(n) necessity luxury item small ticket item unaccountable expense

The graph shows how many words per minute two students read. drag to the table the unit rate that matches each graph.

Which of the following is the major negative aspect of crossover designs for research studies? a. prohibitive cost b. residual effects c-subject drepout d. incomplete randomization e. large sample size required